Drilling machine



Nov. 2 1926. 1,605,714

G. H. GILMAN ISRILLING MACHINE Filed Jan. 31, 1920 2 sheetsheet 1 mWl mm mw s mm, wm S u ,y mw n R t ww 5 -IIIMV llll l 1h i I e W |v||||||.1IN..|...,/ ,Il wl t -lml 1 l i @m wf w Q me@ J9/7 Q E. m3. w M wm, mm mi mm mw @www @M lxlll .QRW #Imwlmv @n @n up bm mw B W OW vw uw um mw. m wn mw VIM 4 n m Ik Ww l MHH w N \M. um vh mm www m. n R R u Q www. w|.\ ...Q mili lli --.fWwMe o\ ww w m\ WQ III I r mw mw mm m. bm www m wm WK Wm w .Mib MWW nm mw w nw I 1,605,714 cs..v H. GILMAN DRILLING MACHINE 2 men-sheet 2 ln'veni'o.- I

Geovgell (Zwaan, j s.

Filed Jan'. 31, 1920 Nov. 2 1926,

Patented Nov. 2, 1926.

lait-5,714

VPATENT ori-"ica` GEORGE H. G'ILMAN, 0F BOSTON, MASSACHUSETTS.

DRILLING MACHINE.

Application filed January 31, 1920.

My invention relates to drilling machines, and particularly` but not exclusively to those for drilling rock, coal and like formations. It comprehends a machine including mechanism for impart-ing to a drilling` tool either or both an angular and a linear motion or force and in which said mechanism is arranged to form a convenient and compact organization; and further comprehends a convenient arrangement for distributing and controlling the fluid supplies.

My invention will be' best understood from the lfollowing specification and accompanying drawings, which disclose a specific embodiment of my invention submitted for illustrative purposes, the scope of which will be more fully pointed out in the appended claims.

In the drawings:

Fig; 1 shows a longitudinal section of a drilling machine embodying my invention.

Fig. 2 is a section on the line 2 2 of Fig. 1; and

Figs. 3, 1 and 5 respectively show sections on the lines 3-3, 4 4 and 5-5 of Fig. 2.

In the embodiment of my invention herein submittechl provide a cylinder 1 having a front head structure, indicated as a vwhole by the numeral 2, and a r-ear head structure` indicated as a whole by the numeral 3. In the front head structure is supported a drilling tool 4 to which a linear force or motion is imparted by a piston 5, and au angular force or motion by a motor which in the submitted embodiment of my invent-ion comprises the gear members 6 and 7. As submitted, the drilling` tool 4 is a drill steel adapted to cut by percussive and rotative action. the percussive action being imparted thereto by the piston 5 which, for this purpose, is mounted for reciprof'ation in -a piston chamber 8; formed in the cylinder member` and is provided with an extension or hammer bar 8 which extends into a chamber 21 in the front head structure and is adapted to strike the tool.

Herein the motor for imparting a rotative action to the tool is .located rearwardly of the rear end of the piston chamber 8 in the rear cylinder head structure. while t-he reduction gearing hereinafter'referred to. which operatively connects the motor with the tool supporting chuck 9. is located ferwardly of the front end of the piston chamber S in the front head structure.

Serial No. 355,494.

For admitting and exhausting motive fluid for causing the piston to reciprocate, any suitablermeans may be employed. That shown herein is not claimed in this application and only will be described with fullness sufficient to set forth how it is applied to the embodiment of my invention now under consideration. n

As illustrated the piston is provided with an internal chamber 10, adapted to be supplied with motive fluid through a preferably stationary plug 11 of tubular formation providing a conduit 12 having lateral ports 13 adapted to be partially or fully closed by the reduced bore 14; of the piston chamber which the plug fits. Extending through the wall of the piston and ,affording communication between the internal chamber and the groove 15 on the exterior surface of the piston is a passage 16 which, when the piston is in the forward end of its stroke and after the ports 13 are throttled or closed, establishes communication between the interior piston chamber and the front end of the cylinder by means of the groove 17 formed in the interior surface of the cylinder.

When the piston is at the rear end of its stroke` motive fluid entering the interior piston chamber 10 by way of the conduit 12 and its ports 13 passes to the rear end of the cylinder through the grooves 18 on the exterior surface of the plug.

When the piston is in the forward end of its stroke, motive fluid from the rear cylinder chamber exhausts through an exhaust port 19. wh-ilethe hammer bar 8 is so formed that when the piston is atl the rearward end of its stroke, said hammer bar withdraws from the bore 20 of the front cylinder head and permits the motive fluid at the front end of the cylinder to pass into the chamber 21 in the front cylinder head whence it may eX- haust to the atmosphere or to the bore 44 of the drill steel.

1 vmay in addition to the means just described, also control the admission or exhaust of motive fluid by means of a valve such as is termed in the art a distributing valve. ythat is to say, a valve independent of the piston which controls all or part of the events or periods of the fluid cycle. As is obvious` l may cause the operation of the piston by fluid controlled by this valve alone. The valve in the embodiment submitted is in the form of an annular shell valve 23, mountilu uit

ed in the rear head structure and concentrically arranged with the chuck rotating` motor so as to be surrounded thereby. The opening` 24 of the valve serves to establish communication between the motive fluid supply passage 37 and the bore 12 ofthe plug 1]..

The valve is formed with a constant pressure face 25 and a` larger face 26 to and from which motive fluid is admitted and exhausted by means of la kicker passage 27 having port-s 23 and 29 controlled by the piston. Then the piston moves toward the forward end of its stroke, motive fluid is exhausted from the passage 27 through the port 23, which is then uncovered by the piston, the motive fluid passing to the atmosphere when the piston uncovers the exhaust port i9. Wlhen the piston moves toward the rearward end of its stroke motive fluid is admitted Vfrom the interior chamber l0 of the piston to the port 29 byway of the piston port 16 and swore 15- When the piston is at the forward end of its stroke, the valve is at the forward end of its travel and in this position connects the rearward end Vof the cylinder to the exhaust passage 30 by means of a passage 3l formed in the valve casing and a groove 32 formed on the evterior surface of the valve. Further, when in4 this position it admit-s motive fluid bymeans of a passage 34, then uncovered by the rear end of the. valve, to the front piston chamber.

W'hen the piston is at the rearward end of its stroke the valve is at the rearward end of its travel and iin-this position closes the rearward end 3l of the passage 31. It then admits motive fluid tothe rear end of the cylinder by means of a passage 33 formed in the valve casingfand then uncovered by the frontend of the valve,ithe passage 33 commanica tingv with the. passage 3l as may be understood by an inspectionof Fig. v2. Further, whenthe valve and piston are in their rearward positions motive fluid is exhausted by means of the valve from the front end of the. cylinder through the passage 34; which then put in communication ywith the eX- haust passage l30 by means of the groove 32 011th@ Valveln order to increase the capacity of the forward piston chamber and thereby aid in reducing the pressure of the Eair throttled by closure of the ports 13, if this action is availed of, and in any case, to aid in maintaining ythe pressure*,admitted lto said chamber, y may. provide the holes. formed in the cylinder wall and communicating with the groove 417. These holes may if desired vco minunicate with the chamber 36 in the front head structure"further to augment the capacity `of the front cylinder chamber.

It will be `noticed that the hammer bar when reciprocating tends alternately to comcation between the chamber 2l and the atmosphere. rIhis passage which I term a breathen7 passage, also serves to exhaust fluid which may be received by the chambei` 2l if the hammer bar is permitted to withdraw from the bore 20. In the submitted cn'ib-cdiment of my invention the exhaust port i9 hereinbefore referred to, communi- Cates with he passage 22, which, as illustrated by Fig. 2, leads intol the rear head structure waere it communicates with the passage 30 carrying the exhaust discharged by the valve 23. ln this connection it will be understood that sludge, water and other foreign material is liable to collect in the chamber 2l of the front head structure receiving the hammer bar and the rear en d of the drill steel. The passage 22 serves inthe present embodiment of my invention not only as a breather passage f r the chamber 2i' and as an. ef;- haust port if thc hammer bar vfdraws from the bore 20, but also as a drainage passage for the chamber 2l. Expulsion of material collected by the passage 22 is aided by the exhaust fluid discharged into said pasfrom tue exhaust port 19 and likewise may be aided by the exhaust fluid discharged by the exhaust passage 30.

Motive fluid for'operating the machine is supplied to the valve and therethrough to the conduit l2 by means of a passage 37 formed in the rear cylinder head structure.

lThe exhaust passage 30 and the passage 22 hereinbefore referred to may unite in the rear cylinder structure as is shown by Fig. 2 whence they pass to the atmosphere.

F or control-ling the inlet passage 37 and the passages 22 and 3,() I employ a suitable vaive 38 provided with a manipulating handle 3S). rlhis valve as shown is formed with a longitudinal passage l-O for constantly receiving motive fluid from the air line or other notive fluid supply connection, and communicatin with the passage tO is a transverse pas adapted to be placed in comn'iunication with the passage 37,r The valve is p rovided with a second transverse passage l2 adapted to establish communication between a port and the terniinus of the passages 22, Ars this type of valve is ojuite common in the art it is believed that further description of the construction thereof vis unnecessary.

The valve 38 `iust referred to may be manipulated to cut ott bothr the communication between the motive fluid supply and the inlet passage 37 and that between the atmosphere and terminus of the passages 22` 30 and simultaneously therewith to establish communication between the supply passage li and the terminus of the passages 22, 30

as will be obvious from Fig. 2 if the valve is considered as turned in a counterclockwise direction. Under these conditions the hammer does not operate and the motive fluid is led by means of the passage 22 to the chamber 21.

For conducting motive fluid to the work, I form the drill steel 4 with the bore 44 leading to the cutting end thereof and communicating at its rear end with the chamber 21. W hen the chamber 21 is supplied with live air the same will pass into the bore 44 and be discharged in such a manner as to cleanse the work, likewise, under normal operating conditions some of the motive fluid discharged by the exhaust passages 19 and finds its way into the chamber 21 and discharges into the bore 44, while if I permit my hammer bar 8 to withdraw from the bore 20 additional air is supplied the bore 44 from the chamber 8.

As illustrated suitably supported in the rear head is a tube 45 for conducting water or other suitable cleansing fluid to the bore of the drill steel, the tube for this purpose communicating by means of the passage 48, with the chamber 46 supplied with fluid from a connection 47. This tube passes through and is surrounded by the annular shell valve 23, the chuck rotating motor, conduit 12 of the plug l1 and the piston and hammer bar.

To form a front head struct-ure I have shown the front end of the cylinder member l as formed with a flange 49 which supports a corresponding flange portion 50 of the chuck casing 51, the cylinder member.

and the flanges 49 and 50 forming a case for the reduction gearing.

In the embodiment of my invention submitted, the chuck 9 is provided with eXterior bearings 52, 53 at its forward and rearward ends respectively these bearings respectively engaging the chuck casing and the cylinder. Intermediate these bearings the chuck casing is shown as providedwith a gear toothed portion 54 while surrounding this toothed portion is a yoke member 55 having a gear toothed portion 56 in mesh with the gear toothed portion of the chuck. Suitable means may be provided for operating the yoke and for this purpose the opposite ends of the yoke are herein shown as apertured to receive suitable eccentrics 57 which when rotated give the yoke a gyratory motion such as to roll its toothed portion about the toothed portion of the chuck and thereby rotate the latter. For each gyration of the yoke, the chuck is advanced a distance corresponding to the difference of the number of teeth on the respective toothed port-ions and in this way a powerful, compact and efficient speed reducing means is provided.

' The motor for driving the chuck as il- In the flanged portion 60 just referred to,

are mounted bearing members 63, while in the flange 50 of the chuck casing are mounted other bearing members 64, these bearing members serving to support shafts 65 carrying at one of their ends the eccentrics 57 and at the other of their ends the gear members 6. These gear members may be removably secured to the shafts and for this purpose are shown the keys 66 integrally formed with the shafts and coacting with suitable grooves in the gear members.

For holding the cylinder and the flange 61 in alignment I have shown sleeve members 76, which also provide additional bearings for the rearward ends of the shafts, additional bearings for the forward ends of the shafts being provided by the reduced diameter portions 77 of the bores 82 formed in the oppositely extending portions 81 of the cylinder as shown in Fig. 1. These eX- tensions 81 with their bores 82 serve to house the shafts.

Motive fluid for operating the chuck rotating motor is supplied by passages 7 8 leading from the motive fluid supply conduit, said passages being adapted to convey motive fluid to the motor inlet ports 79 formed in the peripheral portion 62 of the motor casing. are provided by the passages 8O extending vthrough the walls of the portion 62.A

The gear members 6 of the chuck rotating motor as illustrated are of smaller diameter than the central gear member 7. In this connection it will be seen from an inspection of Figs. 3, 4 and 5 that herein the chuck rotating motor, its reduction gearing and the cylinder are generally speaking elliptical in outline. It will further be noticed from an inspection of Figs. 3 and 5 that herein the motor and the gearing are substantially of the same size and from an inspection of Fig. 2 that the short axis of the gearing, the motor and cylinder are substantially of the same dimension. As the corresponding long and short axis of the motor, cylinder and gearing are herein superimposed one upon the other in the assembled' machine, a flat sided structure re- Sults which adapts the machine to be used in confined situations.

The supporting means for the machine is shown as a handle member having a base 67 Exhaust ports for the motor s till to which is secured the valve cap 69 and the base 68 of. the plug ll. The cap 69 and base 08 are recessed to receive the valve 2l and together With the projecting portion 70 of the supporting member form a casing for the valve. The handle member base G7, the cap 69 and plug base 68 are suitably apertured to receive the bolts 71', which are provided with heads "2 having flattened portions 72 (Fig. ll) coacting with the interior Wall ot the sleeve 59 to prevent turning ol the bolts.

For holding the front and rear head structures in assembled relation with the cylinder member I have shown yokel members 73. These yoke members are held in place by means of suitable set screws 7l and intermediate their length are supported'by suitable lugs 75 formed on the extensions 8l of the cylinder. i In respect to the means for rotating the chuck the rock drill disclosed herein is an improvement over the inventions disclosed in my copending applications Serial No. 350,577, liled January l0, 1920 and Serial No. 354,536, liled January 28, 1920.

It Will be understood that I am not limited to the embodiment of the invention discloset herein and that Within the scope ot the invention Wide deviations may be made therefrom Without departing from its spirit.

Claims:

l. In a drilling machine, a cylinder, a rotary chuck, a drilling tool carried by said chuck, a rear cylinder head comprising an annular motor casing, means for supplying said cylinder Wit-h motive Huid through the interior of said annular casing, motor means in said motor casing for rotating said chuck, and an operative connection between said motor and said chuck.

2. In a drilling machine, a cylinder, a drilling tool, a rear cylinder head, a motor housed by said rear cylinder head, said motor comprising a plurality of meshing gear members one of which is parallel to the axis of said cylinder and is carried by a shaft ei;- tending longitudinally of said cylinder, chuck means adjacent the :trout end ot the c vlinder for rotating the tool, and a high 'atio speed reducing connection between said inc-ans and shaft.

3. In a drilling machine, a cylinder, a gear .member located substantially coaxially therewith and rearwardly thereof, a second Fear member meshing with the lirst gear nomber and being parallel thereto, a shaft driven by said second mentionedy gear member, a chuck located adjacent the front. end of said cylinder, and high ratio reduction gearing oft the `gyratory type for o1 eratively connecting said chuck and said shaft.

4l. In a drilling machine, a cylinder. front and rear head structures mounted on said cylinder, a fluid operated rotary motor housed in one ot said structures, said motor delivering'continuous uni-directional motion and being arranged coaxially oi said cylinder, high ratio speed reducing gearing housed in the other of said structures, and driving means connecting the motor and gearing.

In a drilling machine, cylinder, front and rear head. structures mounted on said cylinder, spaced oppositely rotating gear members housed in one ot said structures, high ratio reduction gearing comprising an annular gear mounted for gyratorymovement about the axis of said cylinder housed in the other of said structures, shafts carrying said gear members ant. being driven thereby, and driving means between said shafts and gearing.

6. A drilling machine having in combination, a cylinder, a piston in said cylinder, a distributing valve `for controlling motive fluid for actuating said piston, a chuck, a motor 'for actuatiru said chuck, reduction gearing connecting said motor and chuck, ahead structure housing said valve and motor, said motor having an annular membcr operated upon by pressure Huid and located substantially coaXially with said piston, and .aid distributing valve being surrounded by said annular member.

7. In. a drilling -machine, a cylinder, a piston in said cylinder, a distributing valve for controlling` motive Huid for actuating said piston, a drill rotating motor, said motor surrounding and'being located coaXially With said distributing valve.

8f A drilling machine 4having in combination, a cylinder, apiston in said cylinder, a distributing valve vfor controlling motive fluid for actuating said piston, a drill rotating motor comprising an annular rotary member for convert-,ing the energy of pressure fluid into Work and located substantially coaxially with said piston, said annular member surroundingsaid distributing valve.

9. In va drilling machine, a cylinder, a piston in said cylinder, a distributing valve for controlling motive fluid `tor actuating said piston, a casing therefor, a drill rotating' motor comprising rotary member Jfor converting the energy of pressure fluid into vvork, said member being rotatably mounted on said casing and surrounding said distributing valve.

l0. In a drilling machine. a drilling tool, a cylinder having a piston chamber. a piston in said cylinder for operating said tool, a chuck, a reversible drive for said chuck comprising a fluid actuated motor and spur rcductiojn gearing, said motor comprisinga spur gear member. said member being located rearwardly of said chamber and having continuousrotation. said reduction lgearing comprising a gear having a gyratory movement located forwardly of said chambemand a shaftlongitudinally disposed with relation to said cylinder carrying said spur gear member and operatively connected to said gearing.

11. In a drilling machine, a drilling tool, a cylinder having a piston chamber, a piston therein for operating said tool, a chuck, a reversible drive for said chuck comprising a fluid actuated motor and spur reduction gearing, said motor comprisimg` a spu gear member, said member being loc-atedv rearwardly of said chamber, said reduction gearing comprising a gear having a gyratory movement, and a shaft longitudinally disposed with relation to said cylinder carr in@ said s ur ear member and o Jeratively connected to said gearing.

12. In a drilling machine, a drilling tool, a cylinder having a piston chamber', a plurality of shafts longitudinally disposed with relation to said cylinder, a fluid actuated motor comprising spur gear wheels located rearwardly of said chamber, high ratio reduction. gearing of the gyratory type for rotating said tool located forwardly of said chamber, said spur gear members and gearing being operatively connected to and carried by said shafts.

13'. In a drilling machine, a drilling tool, a cylinder having a piston chamber, a plurality of shafts longitudinally disposed with relation to said cylinder, meshing gearmembers having continuous rotary motion and being located rearwardly of said chamber, high ratio reduction gearing for rotating said tool and being located forwardly of said chamber, `and said gear members and gearing being operatively connected to said shafts.

14. In a drilling machine, a cylinder, front and rear head struc-tures therefor, a chuck, a chuck rotating motor delivering continuous uni-directional moti-on and located in said rear head structure, a high ratio reduction gearing operatively connected to said motor and chuck located in said front head structure, said reduction gearing comprising an annular gear gyrated about the axis of said chuck and cylinder, said motor and gearing each having a long and short axis, and the corresponding axis of each being substantially superimposed whereby is afforded a flat sided arrangement of the enumerated superimposed parts.

15. In a drilling machine, a cylinder,

front and rear head structures therefor, a

chuck, a chuck rotating motor delivering continuous uni-directional motion and located in said rear head structure, a high ratio reduction gearing operatively connected to said motor and chuck located in said rear head structure, said Oearing comprising a gear mounted for gyratory movement about the axis of said cylinder and chuck, said cylinder, motor and gearing each having a long and short transverse axis, and the front head structure, said motor and gear-l ing being reversible, said head structures each having a long and short axis, and the corresponding axis of each being substantially superimposed whereby is afforded a flat sided arrangement of the enumerated superimposed parts.

17. In a drilling machine, a cylinder, front and rear head structures therefor, a chuck,y

a chuck rotating motor delivering continuous uni-directional motion and located in said rear head, structure, a high ratio reduction gearing of the gyratory type operatively connected to sai-d motor and chuck located in said front head structure, saidy motor and gearing being reversible and eac-h having a long and short axis, and the corresponding axis of each being substantially superimposed and embraced Within the projected confines of the other whereby is afforded a. flat sided arrangement of the enumerated superimposed parts.

18. In a. drilling machine, a cylinder, front and rear head structures therefor, a chuck, a chuck rotating motor delivering continuous uni-directional motion and located in one of said head structures, a high ratio reduction gearing of the gyratory type operatively connected to said motor and chuck located in the other of said structures, said gearing comprising an annular internal gear meshing with an external gear for said chuck, said head structures each having a long and short axis, and the corresponding short axis of each being substantially superimposed and embraced within the projected confines of the other whereby is afforded a flat sided arrangement of the enumerated superimposed parts.

19. In a drilling machine, a cylinder, front and rear head structures therefor, a chuck,

a chuck rotating motor, delivering continuous uni-directional motion and located in one of said head structures, a high ratio reisov 20. In a rock drill, 'a cylinder,l a hammer piston in said cylinder, a chuck,-a drill steel caried by said chuck and actuated by said piston, front and rear head structures for said cylinder, a reversible `motor and reduction gearing for said chuck, said motor comprising three meshing gear members in said rear head structure, said gearing comprising an annular gear surrounding said chuck and through which percussion is imparted to Ithe bit of said drill steel, and eccentric means driven by said motor for giving said gear a ,gyratory motion about said chuck.

l 2l. In a rock dri-ll, a cylinder, 'a hammer piston in said cylinder`v a front -liead structure having therein a chuck mounted for rotation relatively to said cylinder, a. Vdrill steel carried by said chuck and actuated by said piston, an external spur gear lfor said chuck, an internal spur gear surrounding saidexternall spurgear and meshing therewith a pair of eccentrics in said tronthead structure at opposite sides of said chuck, said eccentrics carrying said internal gear, shafts carrying said eccentrics and extending rearwardly beside said piston to'a rear cylinder head 'for said cylinder, three meshing gear `members in said-rear head, tiro-of said gear members being carriedby said shafts andthe other being in the 'form of a ring coaxial Awith said cylinder, a casing surrounding said gear members, means yfor admitting motive fluid to said casing for operating 'said gear members, and means `for admitting motive fluid for actuating said piston through saidgear member in the form of airing.

'22. In a rock drill, a cylinder, a hammer pistonin said cylinder, a front head structurelhaving therein a chuck mounted for rotation relatively to said cylinder, a drill steel carried by said chuck andactuated 'by said piston, anexterna'l spur gear for said chuck, an .internal spur k,gear surrounding said external spur gear and meshing therewith, a pair of'eccentrics in said front'head structure at opposite sides of :said chuck, said eccentrics carrying Vsaid internal gear, shafts carrying said eccentrics and extending rearwardly beside said piston to a rear cylinder head for -said cylinder, three meshing `gear members in said rear head, tivo of said gearunembers being carried by` said shafts andthe-other being in the lormof a ring coaxial With said cylindeiaa casing surrounding said gear members, means gfor admitting motive `fluid to said casing `for operating said ,gearmembers and a distributing valve for said `piston surrounded by said gear member in the form of a ring.

Q3. drilling machine having in combination, a cylinder, a piston insaid cylinder, a distributing valve for the motive fluid actuating said piston7 ya casing for-said valve, a chuck, a ychuck,rotating Vmotor comprising a rotary fluid actuated member, reduction gearing connecting said motor and chuck, and said member surrounding said casing.

24. AA drilling machine having in combination, a cylinder, a piston in sai-d cylinder, a distributing valve for the motive fluid actuating said piston, a casing for said valve, a chuck, a chuck rotating motor comprising an annular member, reduction gearing connecting said motor and chuck, said member surrounding said casing, anda head structure for said cylinder surrounding said casino".

25. In a drilling machine, a cylinder, said cylinder having a chamber containing a piston, means for admitting and exhausting motfve fluidfto and from said zcylinder .includine' a 'hollow valve located exteriorly of the `cy nder chamber, other means for conducting motive 'fluid to said cylinder including` a passage extending through said valve, land means for conducting vfluid to the Work including a conduit extending through said valve.

26. ln a drilling machine, a cylinder, a piston, means for admitting and exhausting motive fluid to and from said cylinder' including a'bar providing a conduit extending into said cylinder, means to conduct fluid to the Work, said last mentioned means'including ya conduit extending through said first mentioned means, and a distributing valve controlling the motive fluid yfor actuating said piston carriedfby said bar.

Qi'. ln a drillingY machine, a cylinder, a piston provided With a motive 'fluid chamber, a bar extending into saidcylinder and providing a conduit connecting said chamber with a lsourceof motiveiluid supply, means for 'conducting 'fluid to the Work, said last mentioned means including a conduit extending through said lirst mentioned conduit means, and a distributing valve /controlling the motive fluid `for actuating said piston carried by said bar.

28. In a drilling machine, Va cylinder, a piston, lmeans for admitting and exhausting motive fluid to and from said cylinder including means providing a conduit extending` into said cylinder, means to conduct Huid to the Work, said last mentioned means including a conduit extending 'through said first mentioned means, and a hollou7 distributing valve the interior of which forms part of said lirst mentioned conduit surrounding said last mentioned conduit.

In a drilling machine, a cylinder, a piston therein ,provided With a motive lluid chamber, conduit means connecting :said chamber with a source of motive fluid supply, means for conducting fluid to the work, said last mentioned 'means including a tube extending through said Vtirstvmentioned conduit means, a hollow distributing valve the interior of which forms part of said conduit means, and said valve surrounding said tube.

30. In a drilling machine, a cylinder, a piston therein provided with a motive fluid chamber, a tubular member connecting a source of motive fluid supply 'with said chamber, a hollow drill steel, and means for conducting fluid to said steel including a tube passing through said tubular member, a hollow distributing valve the interior of which is in fluid communication with said tubular member, and said valve surrounding said tube.

3l. In a drilling machine, a cylinder, a piston, a valve for controlling the motive fluid for actuating said piston, a chuck, a hollow drill steel carried by said chuck, a motor for rotating said chuck having an annular rotary motor member surounding` said valve, and a tube for conducting fluid to said hollow steel and passing through said valve.

32. In a drilling mechanism, the combination with fluid pressure operated mechanism 'l'or imparting a blow to a tool, of means providing a plurality of chambers for receiving said mechanism, a hollow drill steel communicating with one of said chambers, a breather passage for the last mentioned chamber, and an exhaust port for another of said chambers communicating with said breather passage.

33. In a drilling mechanism, the combination with fluid pressure operated mechanism for imparting a blow to a tool, of means pro viding a plurality or chambers for receiving said mechanism, a hollow drill steel communicating with one of said chambers, a breather port for the last mentioned chamber, one or more exhaust ports for other of said chambers, and conduit means connecting said ports to each other and to the armosphere.

34. In a drilling machine, a piston,l fluid pressure means for operating said piston including an exhaust port, a tool holder, a hollow drill steel supported by said holder, a drainage passage for said holder, and conduit means connecting said exhaust port to said holder.

In a drilling machine, a tool holder, a hollow drill steel supported by said holder, a drainage passage for said holder, and means to aid the discharge from said passage including` conduit means for injecting fluid thereinto.

36. In a drilling mechanism, the combination with fluid pressure operated mechanism for imparting a blow to a tool, of means providing a plurality of chambers for receiving said mechanism, a breather passage for one of said chambers, an exhaust port for another of said chambers communicating with said breather passage, conduit means connecting said breather passage to the work, and means for connecting said passage to a source of fluid pressure.

37. In a drilling mechanism, the combination with fluid pressure operated mechanism for imparting a blow to a tool, of means providing a plurality of chambers for receiving said mechanism, a breather port for one of' said chambers, one or more exhaust ports for other of said chambers, conduit means connecting said ports to each other and to the work, and means for connecting said conduit means to a source of fluid.

38. In a drilling` machine, a piston, fluid pressure means Jfor operating said piston including an exhaust port, a tool, a tool holder, a hollow drill steel carried by said tool holder, a drainage passage for said holder, conduit means connecting. said exhaust port to said holder, and means for connecting said drainage passage to a source of fluid.

39. In a drilling machine, a chuck, a hollow drill steel carried by said chuck, a passage for connecting the chamber of said chuck with the atmosphere, and means for interrupting such connection and supplying pressure fluid to said passage.

40. In a drilling machine, a chuck, a hollow drill steel carried by said chuck, a passage i'or connecting said chuck with the atmosphere, and a single valve for interrupting such connection and supplying pressure fluid to said passage.

ll. In a drilling machine, a hollow drill steel, a hammer motor for operating said steel, an exhaust passage for said motor in, continuous communication with said steel, and means for at will supplying live pressure fluid to said passage.

42. In a drilling machine, a chuck, a hollow drill steel carried thereby, a chuck rotating motor, a hammer motor, an exhaust passage for said hammer motor connected to said hollow steel, an intake passage for supplying both of said motors with operating fluid, and a valve for supplying live fluid to said exhaust passage and for interrupting the supply to said intake passage.

Ll2. In a drilling machine, a chuck, a hollow drill steel carried thereby, a chuck rotating motor, a hammer motor, an exhaust passage for said hammer motor connected to said hollow steel, an intake passage for supplying both of said motors with operating fluid, and a valve for controlling both of said passages and having a position wherein the exhaust passage is supplied with live fluid.

ll. In a percussive rock drill, a cylinder, a chambered piston in said cylinder, a hollow drill steel operated by said piston, a tubularr member carried at the rear of said cylinder and extending into said piston, a distributing valve carried interiorly of said tubular member, and a cleansing fluid tube extending through said valve and said tubular member.

45. In a drilling machine, a hammer cylinder, a piston hammer, a chuck, a motor for rotating said chuck, said motor carrying a distributing valve for said hammer, a casing for said distributing Valve, and said motor and distributing valve forming a rear head for said cylinder.

4G. In a drilling machine, a hammer cylinder, a hammer piston, a chuck, a chuck rotating motor, a distributing valve for said hammer, said Valve being arranged coaxially with said hammer, said motor surrounding said Valve, and a casing for said Valve and motor forming a rear cylinder head for said cylinder.

47. In a drilling machine, a hammer cylinder, a hammer piston in said cylinder, said hammer piston having a head With an exterior rearward Working pressure surface and an exterior forward Working pressure surface, a motor carried by said cylinder rearwardly of said piston head for rotating said chuck, said motor having an annular rotor, and said rotor surrounding means for controlling` the flow oi motive fluid to opposite sides of said piston head.

In testimony whereof, I have signed my name to this specication.

GEORGE H. GILMAN.

Certicate of Correction.

It is hereby certified that in Letters Patent No. 1,605,714, granted November 2, 1926, upon the application of George H. Gil1nan,of Boston, Massachusetts, for an improvement in Drilling` lvlachines, errors appear in the printed specication requiring correction as follows: Page 5, line 8S, claim 17, after the Word head strike out the connna; page 7, line 96, claim 40, after the Word connecting insert the Words HL@ chamber of; and that the said Letters Patent should be read With these corrections therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 4th day of January, A. D. 1927.

[SEAL] M. J. MOORE,

A 'rtz'ng ommz'ssoner of Patents. 

